Phonograph apparatus



Feb. 2, 1954 B. B. BAUER PHQNOGRAPH APPARATUS 2 Sheets-Sheet l Filed April 50, 1949 e/r, Wl

8 m Wr A l l INVENTOR. Bergamzzz, E czuef `BY.

Y af- Feb. 2, 1954 B. B. BAUER Y 2,668,196

PHONOGRAPI-I APPARATUS Filed April 30, 1949v 2 Sheets-Sheet 2 I IN V EN TOR. e/yamm 5. 56u10' Patented Feb. 2, 1954 PHON OGRAPH APPARATUS Benjamin B. Bauer, Oak Park, Ill., assgnor to Shure Brothers, Incorporated, Chicago, Ill., a corporation of Illinois Application April 30, 1949, Serial No. 90,687

Claims.

This application is a continuation-in-part of the application of Benjamin B. Bauer, Serial No. 771,433, filed August 30, 1947, entitled Phonograph Apparatus, and the invention hereof relates to phonograph translating devices, more particularly to such apparatus for reproducing sound from records, and it is an object of the invention to provide improved apparatus of this character.

Phonograph translating devices for reproducing sound from records, termed pickups, frequently are in the form of cartridges which comprise a casing having a translating element and a coupling structure therein. Terminals in the form of prongs connected to the translating element extend from one end of the casing for easy and rapid insertion into corresponding sockets in the phonograph tone arm. A record engaging needle or stylus is arranged to project through the casing adjacent the other end for following record grooves, the stylus being attachable to the coupling structure by means of a screw, for example, usually also projecting from the casing where it is engageable by hand or with a tool. The coupling serves to transmit mechanical movements or some function thereof from the stylus to the translating element, and the translating element serves to convert the transmitted mechanical movements into electrical variations which are transmitted through the cartridge terminals to the phonograph amplifier or other reproducing device. For high quality reproduction, the sound output from the phonograph should be substantially free from extraneous noises such as needle and record talk which are sounds radiated directly to the atmosphere because of the vibrations of the stylus, the coupling structure, and the record itself.

Accordingly, it is a further object of the invention to provide a pickup embodying improved stylus and coupling structure whereby extraneous noise due thereto is reduced to a minimum.

It is a further object of the invention to provide an improved phonograph pickup wherein the transducing element functions by being placed under simple bending stresses.

It is a further object of the invention to provide, in a phonograph pickup, an improved coupling structure between the pickup stylus and the transducing element.

It is a further object of the invention to provide, in a phonograph pickup utilizing a piezoelectric element functioning by being placed under simple bending stresses, an improved coupling structure between the pickup stylus and the piezoelectric element.

There have been developed phonograph record players utilizing a very ne groove, commonly termed a. microgroove, records having such microgrooves requiring a yneedle or stylus having a much finer point than do records having ordinary grooves. Consequently, if it is desired to change from a record having a regular groove to one having a microgroove, it is necessary to change styluses as well. This is disadvantageous. Accordingly, it is a further object of the invention to provide an improved pickup, for phonograph records of the character indicated, embodying structure wherein both types of styluses may be mounted thereon.

It is a further object of the invention to provide an improved phonograph pickup ofthe character indicated'having provision for two styluses.

In carrying out the invention in vone form, a phonograph translating device has been provided comprising, a casing, a piezoelectric element mounted in the casing for bending deformation, a vertical rotational member mounted in the casing including means at one end for receiving a stylus, and coupling means between the piezoelectric element and the vertical rotational element whereby the piezoelectric element is placed in bending stress upon rotation ofthe vertical rotational element.

For a more complete understanding of the invention, reference should be had to the accompanying drawings in which:

Figure 1 is a vertical sectional View of a pickup embodying the invention;

Fig. 2 is a sectional view taken substantially in the direction of arrows 2-2 of Fig. 1;

Fig. 3 is a front elevational view' taken substantially in the direction of arrows 3-3 Y of Fig. 1;

Fig. 4 is a sectional elevational view of another embodiment of the invention;

Fig. 5 isY a sectional elevational view of a furtherembodiment of the invention; and

Fig. 6 is a sectional view taken substantially in the direction of arrows 6-6 of Fig. 5.

Referring to the drawings thereare shownAv lating members are arranged therein for suit'y ably supporting prongs and 16. The-structure i for placing crystal 56 under bending stress'is arranged at the end of the. pickup oppositeto prongs 15 and 16, and conformingtothisfsup@ porting pad 68 is placed in between the crystal extremities in order that the for-.Ward extremity may be bent back and forth. For this purpose,

crystal 66 is mounted with its nat side'-A verticali in the casing.

At the extremeforward end ofthe pickuprthe casinghalves are provided with suitable openings .in-which may be received resilientsupporting members 11 and 18, the axis l:for'these members and openings being verticalof the pickup. Centrally held Within resilientmembers 'Hand 13 isa .vertical rod 19 Yhaving an enlarged portion 8l substantially at its'center. The lowerend of rod 19 extends 'outwardlyfof the pickup-and is adapted to have av stylus attached nthereto as will be explained hereinafter. A hole is drilled through portion 8l transversely. with respect to rod-.19 and-a'driving member or paddle 82 is pushed therethrough so that itsforward end 83 extends into a recess 84 provided in the pickup casing. The rear end of paddle 92 consists of a flattened'portion surrounding. Whicha resilient spacer 85 is placed. A connecting link B16-is bifurcated ateachend-in order that it may grip paddle 82k and at the same time grip the Lorward end Aof crystal 66. K

It will be apparent from` this construction that Whenever rod 19-is rotatedfabout its axis, paddle 82 is oscillated to and fro and moves the en`d of crystalsideWise with it. Spacer 85 absorbs some undesirable vibrations andcushions shocks.

At Ythe lower end or rod 19`projecting outwardly of -the casing, an enlarged portion B'lis provided which is threaded and which has-aholedrill'ed therethrough `in amanner described inthe parent appu'cationjseriai No.' 711L433g Stylus 88 placed Within thehole "in" the enlarged portion B1, and"a'"nut'89iholds"the"stylus to the stud' as uescrb'ed'in thejparent application. When the point-of stylus' engages areco'rd having" lateral grooves' therein,` the end" of' the stylus moves toandfro sidewise and accordingly causes'rodl 9` to' rotate back'and forth; thisrotational movement placing the crystal underb'eriding. stresses. y y

Connecting link {i6-may' be'shifted intov different positions relative to" thefaxi'siof rod-'19 l"thereby changing the' distance la that* is;A the* distance from rod "19 `to the point where-link 86"- engages the paddle. Changing' theidistance I2 relative to the distance-li, ie; thevlength from the axis ofrod 19 -to the pointiof l'the stylus '88; varies the leverage exerted' by the stylus and thereby greater or lesser bendingforces'may be obtained, as Vde`I .sired. In addition to theiistrongbendingferce `obtained by this constru'cticxrr, -thefedective' rass ,and stiffness is reduced, i.J ebytheratiol I/ l i) 2; Thisfis advantageousfin that'a moreifaithuliref spense f isV produced. in-thevcrystal output.-

The rodfl19` rotates aroundf. its verticaiaxis: Its 'effective moment-ofinertia `isf-small fandfthe contribution of its lmassfto Fthefmasssat thegastylus point is therefore small. In this manner, a pick- 4 up is produced which has high compliance and good output and yet one which has an extremely small needle mass and stiffness.

In order that excessive movements of rod 19 may not injure crystal 65, the recess 94 in the forward! end of the pickup isfso constructed that the'end 83"of pad'dle 82 engages the'sides'of recess p 55 whenever the desired limits of movement are exceeded.

Stylus-89 is prevented from being injured by excessive vertical movements by studs or prongs Stextendingi'downwardly from the forward end of thefcasi'ng along each side of the stylus as may`-beseenr -best Fig. 3.

Theembodiment of Fig. 4 is similar in its general arrangement to the embodiment of Figs. l,

2 and B-,andE difers therefrom mainly in that the construction is such that the pickup may be used fortwo-'sided operation. Toithisend crystal 92 is supported inside of a casingccomprisingtapairv of members. Ati the forward' end olthe" pickup casing,.asha-ft 93 isarranged tov'besupported in suitable openings bymeans of resilient' bearing members 94and- 95. Each end of` therod orrshaft L93r projects outwardlyof the casing and includes respectively enlarged portionsySB- and 91 which are threaded and have holesfdrilled therein to receive-styluses 98 Vand 99in-amanner described Ain the parent-application; v The angularpositioncfshaft 93 madesuchthat when two identical styluses-98 and 99are used, the points thereofliejina lineperpendicular to the horizontal axis of thepickup andpoint in opposite'directions, this Ibeingadvantageous in order that the same lrelative point in a yrecord may he engaged-by eitherl` stylus irrespective of which side of the-pickup is being used,` providedthat the record rotates in onedirection forione stylus and in Vanother direction for theother stylus. y

Intermediatetheends ofrod-'B there is an enlarged portion Illi through Which'a hol'extends to receive a paddle fm2, the paddle having a"fo`r`' Ward end 193 received ina suitable recess inftlie casing to preventV excessive movements of rod 93. 'Ihe rear end ofp'addlelll?` is "covered vWith a piece of spacingmateri'al fl 08"and 'is"cn"n`ectd to crystal 92 bymeansbfabifrcatd'rrinbe'l (M Accordingly; it'Will'be Serth'at lateral A1i'1(2-\e'`y mentiof styluses"98arf1'd 99 effect 1a rotational movement of shait"93"an d"f paddle |02, thereby' placing crystal 92'under berrdingstresses The styluses'e ldhd99 `ldite somewhatifm thestyusesofl Figs? lj 2`and"3 ina-smucirasthese styluses are held in rod" 93' which extends "at 'fari acute angle "relative to the 'axis of-= the pilfup rather thanati righanglfes theretoj Secondly;- the Arear or attaching' portion I 95' of the stylii'ses is'ben't upv/"ardlyatian'arigie relative'tothe fr-'l Ward orourvedportion.'A Ther-'curved portions' 'of stylusesl Siand` e 9 'fare 'similar to the cuvedffore' ward -portionsfof "the-:sty1useecr-rigsf 1', ziaria 3, the only` diiferen'cefbeing in" bending`-` thereari Ward portion so that the' styluses Will`assir'ne proper positions. A

The upper`and`lowermembers of the casi'ngjare also provided 'with projeenr'rgmemtei-s" let-:arid ie? on eachsideof thelstylses 'to'pi'eientex cessive vertical movementthereof.n

l Hl and -i l2 Within which-there supp'orteda crystal or other piezoelectric elementi l3,' -Eiezo electric element H3 is mounted as a cantilever previous embodiments. f

At the forward end of the pickup there is ayer,-` tlcal member or rod I |4 mountedfor. rotation in rubber or other resilient material bearings I| and IIB. Each end oi rod ||4 projects through vcasing` H0 and is provided with .structurefor holding styluses ||1 and H8, as described in the parent application; .Substantially `centrally of -rod I I4 there'is an extension I I9 rigid therewith, which extension cooperates vwithlyoke |2| for transmitting rotational movements of rod |I4 as 'bending movements tojcrystal ||3. Yoke |2| .maybe formed ofv a thin materialstamped and -bent into the configurationshown. The yoke has bifurcated portions at one end which are received 4.around the forward orfree end of the. crystalsa -iiexible pad |22 of rubber or similar material being placed between the bifurcations of the yoke :and the outside of Ythe crystal in order to lend some resiliency to this coupling. Likewise, a layer v|32 lof flexible material surrounds extension IIS so that the engagement betweenthese two members also is somewhat resilient. v

Similarly to the embodiments described, to and -fro movements of thestylus pointshII'I and ||8, when either one of these is being used, will produce rotational to and fro movements of rod III: which in turn will produce bending movements of the forward end of the crystal through the extension IIS and yoke |2|.

To assure that excessive movements or the crystal ydo not occur, thereby to prevent breaking, an extension |23 is provided on the frontward side of rod-H4. Extensionv |23 is received within a recess |24 having predetermined dimensions so ythat when movements of rod I|4`beyond a cer tain maximum tend to occur, extension |23 engages with the side walls of recess |24 and thereby limits furtherlmovement.l

The record engaging points of styluses I|1 and ||8 may bedifferent so that one may be used for` cooperating with a microgroove record and the other may be used forcooperatingwith an ordinary record, the records rotating in the same direction. When a particular type of record is being played, it is only necessary to pull out pickup III) and so place it that the proper stylus is in a position to engage the record. The pickup is then placed into active position by inserting the connecting prongs |25 and |26 into the sockets provided therefor. Prongs |25 and |26 may not be sufficient for supporting the pickup, and a pair of wings or brackets |21 and |28 may be attached to the forward end of the pickup, as shown, by rivets |29 to provide additional support. Wings |21 :and |28 include openings |33 and |34 respectively for receiving attaching screws.

The pickup is simply reversible, that is, after one stylus has been used and it is desired to use the other one, it is necessary only to turn the pickup over.

For protecting the points of styluses ||1 and I8, downwardly projecting pairs of tusks |35 and |36 may be provided.

Crystal ||3 is supported in the casing at its rearward end by a pair of flexible pads |31, and approximately centrally of its length by a second pair of pads |38. The front end of the crystal is free so that deflections thereof may occur. With the construction as shown, deflection of the forward end of the crystal produces relatively simple bending stresses. Crystals may be formed sufliciently thin so that bending stresses of the charwith its flatfsidevertical, also" similarly-to the 6 acter indicated result in sufficient electrical'out putI. y

The points of styluses ||1 and I I8 lie on va line perpendicular tothe axis of the pickup, and the styluses point in the saine direction, it being intended that the pickup be turned over if a different stylus is to be used. z While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not liinitedrthei'etov since many modications may be made, and it is, there-V fore, contemplated by thek appended4 claims to cover any such modifications as fall withinjthe true spirit and scopepf the invention. n

The invention having thus been described, vwhat is claimed and desired to be secured by Letters Patent is: r

1. In a mechano-electric transducingrdevice, a bender-type of transducing member, support means for mounting said transducing memberrat a portion removed from one end thereof t0 leave said end free, a `driving member, means for mounting said driving member adjacent to the free end of said transducing member and for angular oscillation about an axis extending transversely with respect to the plane of motion of `a p oint of said iree end, a part fixed to said driving member and displaced transversely with respect to said axis, whereby angular oscillation of said driving member produces to and vfro motion of said part, a rigid coupling member having spaced apart arms embracing opposite surfaces of the free end portion of said transducing member and having a portion connecting said arms and extending beyond said free end of said transducing member, said extending portion operatively engaging said part, whereby to and frol motion of said part produces bending deflections of said transducing member, said driving member being apertured transversely thereof to -receive stylus means.

2. In a mechano-electric transducing device, a bender-.type of transducing member, support means for mounting said transducing member at a portion removed from one end'thereof to leave said end free, a driving member, means for mounting said driving member adjacent to the free end of said transducing member and for angular oscillation about an axis extending transversely with respect to the plane of motion of a point of said free end, a part fixed to said driving member and displaced transversely with respect to said axis, whereby angular oscillation of said driving member produces to and fro motion of said part, a rigid coupling member having spaced apart arms embracing opposite surfaces of the free end portion of said transducing member and having a portion connecting said arms and extending beyond said free end of said transducing member, said extending portion operatively engaging said part whereby to and fro motion of said part produces bending deflections of said transducing member, said driving member having two openings therein each adapted to receive a stylus, said openings respectively being displaced axially of said driving member in opposite directions from said part.

3. In a mechano-electric transducing device for use with a phonograph record, a casing, a bender-type of piezoelectric transducing member mounted inY said casing and having one end thereof free for bender-type of operation, a driving shaft adjacent to said free end of said transducing member and having its axis disposed at an angle to said record surface in the normal playingfpositionmaidnrixdngfshaft.belng'mounted in said casing for angular oscillation about said 4axisrand havingcamend portion thereofaextending exteriorly :of said 'easingfa transversely'. projecting Fpartiixed to said driving slaaf-t, and sa. rigidfcoupling member havingrspacediapartmrms embracing opposite surfaces-.'ofzthe.freendmor- .tion :of rsaid -ltransducing fmember .and .having a. portionjoining;saidi'armsitogetherand .extending :boy'oncisaidlI free end. off said1.transducing member, said-:extending portion of said coupling imember being in motionetransmitting relationship with 1mid=part,A saidexteiiineridportion-` of said 'shaft having a transverse opening .therein forirec'eiving .aistylds f4. In a meenam-electric vtransducing Adev-ice for use with a phonograph record, a rcasing, 'ha bender-type of piezoelectric transmiucing I member 'mounted lin -said casing land having `one end vthereefffreeforr bender-type offoperation; aI driving' 'fshaft adjacent said free Y end of 'said trans- 'ducing'member 4Vand having lits axis disposed at an angle ytoxsaidre'tzorcl surface inthenormal 'playingpositionfsaidfdrivingshaft 'havinganend portionthereo'f `Vextendingexteriorlyfoi nsaid easf ing, spaced-a-partcompliant bearings-mountedin said1 casingand-vsupporting-saidf'driving shaftior angular oscillationabout-'saidaxis,a transversely projectingpartxedftosaiddrivingshaft between `said bearings, 'and farigid "eouplingf memberhaving spaced apart farms embracing opposite sur- -faces of the lreefendportion olfA said transducing member and *having a portion joining saidl arms together --and extending A--beyond said free end of saiditransducing member, said extendingportlon of `'said -coupling vmember "being vconnected `in 'motion-transmitting relationship with Saidpart, -said couplingmember-peingfadjustable uponsai'd transducing member 'to `alter 'the 'distance lfrom theaxis'df-'said' driving vshaftto the-'point of connection of said part and said coupling member,

v'said exterior I end portionY of said shaft `having a transverse opening therein1 for receivinga stylus 5. "In Ja mediano-electric transducing `device for use "with fa phonograph xfx'ecoi'd, sa. i casing-1a bender-type of piezoelectric. transducingmember mounted 4in fcasing and having lone l@fend thereof'free ffor bender-type of l operation-'sfA drivl.ing shaft `ai'ijacent "said: free end `,of :sa-id trans- -ducngrmember-vand Shaving its axis disposed generallyrperp endicular :tol .said recordfsurface in the l.normal"praying position, .said driving-shaft 'hrw-V ing :an Lend portion thereof extending -fexteriorly off-:said casing,n spaced L apart compliant bearings mounteddnsadcasing andisup'portingf said :drive ing-.'shaittfor vangular oscillation kabout said =faxis.

`a transversel'y projecting tongueelike `member .iixe'd ltoisaid Y driving shaftbetween isai'dsbearings. .-a frigid Lcoupling vmember :having :spaced 'fanart 'Number Name "Date l Re. 20,680 'Sawyer Mar.' 29,1'1938 2,212,530 Weil Aug. l27,1%() 2,280,763 Hasbrouck Apr.` 2151942 "2,381,861 Bauer -Aug.14,"19'45 2,479,894 Andrews Aug. 23,'11949 '2,484,950 Jaffe "Octtl 1'8, 1949 "2,568,673 Washburn "Septfiflgl FOREIGN VPIVIETINTFS Number Country Date -11488 ,294 GreatBritain .'July'i 1938 536,488i Germany Y-f0ct.`12l,'1933 

